Method of insulating



H. M. AND H. D. ABERNETHY.

METHOD OF INSULATING ALUMINUM COVERED COPPER CONDUCTORS.

APPLICATION FILED APR. 17, l9l6.

1,323,236. Patented Dec. 2, 1919.

insulator and is especially designed for producing an insulator for copper, copper w1re,.

HARRY M. ABERNETHY AND HARRY-DQABERNETHY,

0F CLEVELAND, onionssrenons 0F ONE-HALF TO HARRY FULLER, OF EAST CLEVELAND, OHIO.

METHOD OF INS ULATING ALUMINUM-COVERED COPPER CONDUCTORS.

Specification of Letters Patent.

' Patented Dec. 2 1919.

I Application filed April 17, 1916. Seria1No.91,762.

To all whom it may concern:

Be it known that we, HARRY M. ABER- NETHY and" HARRY D. ABERNETHY, citizens of the United States, residing at Cleveland,

5 in the county of Cuyahoga and State 'of Ohio, have invented certain new and useful Improvements in Methods of Insulating Aluminum-Covered Copper Conductors, of which the following is a specification.

Our invention relates to an aluminum or copper strips.

The main object of our invention is to provide a simple, economical and efficlent method of producing an aluminum insulator for copper, copper wire, or strips, wh ch insulator possesses very high heat-resisting properties, and is practically fire-proof and indestructible by the application of heat.

Another object of the invention is to provide an improved electrolyte solut1on 1n connection with a porous cup filled with mercury for treating a copper wire or flat piece coated with aluminum, and by, the use of a small voltage, and a small amount of electric current, roduce an electrolytically deposited insulatlon that will withstand a puncture test of more than 1,000 volts.

A further object of this invention is to cover a copper wire conductor with a thin coating of aluminum, preferably by casting the aluminum around a copper billet, then rolling .it into rods and drawing down to wire sizes, then subjecting the wire to our improved electrolytic bath, thereby forming on the aluminum an insulation coating of such high resisting qualities that the wire thus leaving a tube. The foregoing and such other objects as may appear from the ensuing description are attained by the novel features and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawing and particularly pointed outin the claims appended hereto, it being understood that slight changes in the form, proportions, and minor details of the structure shown may be resorted to Without departing from the spirit or sacrificing any of the advan tages of the invention.

In the accompanying drawings it will be seen that the figure represents a diagrammay be melted from under the insulator,

matic view of the improved device for carrymg out our invention. I

Numerals of reference are employed to designate the parts shown in the drawing. In the embodiment of this invention as illustrated, the numeral 1 designates a receptacle of any suitable material which is filled with a solutioncomposed of permanganate Nil of potassium or sodium, water, and sulfuric acid, and within saidreceptacle is placed a porous cup 2, of any desirable material filled with mercury, and while a coil .of copper wire with a thincoating of aluminum, a straight piece, orflat piece may be suspended in the bath, constituting the anode of the system, we have shown a piece of wire 3, of a serpentine form, suspended within the solution to which wire 3, is attached one terminal 4, of an electric generator 8, and attached to a piece of metal 5, located within the porous cup 2, which contains the cathode of the system, is the second terminal 6, leading to the generator, and by the use of small voltage and current a coating of insulation is formed on the aluminum coated wire 3, that will withstand a puncture test of veryhigh voltage, and thereby the thin coating of aluminum over the copper wire, or piece, is transformed into an insulator of high heat-resisting substance which is substantially fireproof and almost indestructible by the application of heat, and the wire may be melted from under or within the insulator and it still remains an efiicient insulator.

It will be understood that long pieces of the copper wire covered with a thin coating of aluminum may be drawn through a bath of the electrolytic solution hereinbefore referred to, whereby the said wire will be provided with an insulatlon possessing the qualities herein stated.

It will be readily perceived that an electrical wire conductor thus produced possesses the advantage of taking up less space than the cotton or silk-covered wire commonly used in constructing magnets, motors and generators, besides a greater current carrying capacity, since so much of the aluminum as is not used for insulation purposes adds to the capacity of the copper wire. Further advantages are apparent, not only from an economical standpoint, but from the ease in which a low'voltage is handled as compared with that of high ten sion, and We are enabled to obtain the full carrying capacity of the copper, and in a much less space ascompared with the cotton covered wire in f'general practice. Again, the high heat-resisting insulation quality is greatly appreciated by motor, generator and magnet builders, for the reason that any excess currents heats the wire thus charring the insulation, which at once becomes a conductor causing short circuits and other interruptions.

Having thus described our invention what we claim, and desire to secure by Letters Patent is 1. The method of insulating a copper conductor coveredwith a thin coating of aluminum by subjecting said conductor to an electrolytic bath, composed of permanganate of potassium, Water and sulfuric acid, in connection with an electrical current, the said conductor forming the anode, and the oathode contained within a porous cup, thereby transforming said coating of aluminum into an insulating substance.

2. The method of insulating an electrical conductor covered with a thin coating of aluminum, by subjecting the said conductor to an electrolytic bath composed of permanganate of potassium, sulfuric acid and thereby forming an insulation coating of high heat resisting substance entirely covermg the aluminum coating.

3. The method of insulating an electrical conductor covered with a thin coating of aluminum, by subjecting said conductor to an electrolytic solution within a container, in connection with an electric current of low voltage and a small amount of electric current, passing the electric current from a generator to the anode and from a metal piece within a porous cup filled with mercury forming the cathode to the generator, whereby the outer part of said coating of aluminum is transformed into an insulation coating ofhigh resistance entirely covering the surface of the aluminum.

HARRY M. ABERNETHY. HARRY 1). ABERNETHY. 

